Record changer



1 Shets-Sheet 1 b&

M- A. WALKER RECORD CHANGER Nbv. 29, 1949 Filed May a, 1944 M- A WALKERATTORNEY Nov. 29, 1949 M. A. WALKER 2,489,941

RECORD CHANGER Filed May s,--1944 4 Shee ts-Sheet 2 m ENVENTOR.

M- A- WALKER I BY MW ATTORNEY Filed ma 3, 1944 4 Sheets-Sheet; s

I N VEN TOR.

BY WALKER V MQ ATTORNEY Nov. 29, 1949 A. WALKER RECORD CHANGER Filed May'6, 1944 4 Sheets-Sheet 4 3 4 i m 1 M m M 5 L H a m s- 5 a R U) 4 0 +1 iI f l "a m INVENTOR. H M-A-WALKER ATTORNEY Patented Nov. 29 1949 UNITEDSTATES PATENT OFFICE RECORD CHANGER Milton A. Walker, San Jose, Calif.

Application May 3, 1944, Serial No. 533,819

7 Claims.

The present invention relates to improvements in record changers, andhas particular reference to phonographs designed to allow a plurality ofrecords to be played in automatic succession and without theintervention of any human agency.

While phonographs of this type are well known and in common use at thepresent time, it is proposed to introduce a new method of operationwhich has not been contemplated heretofore as far as I am aware.

More particularly, it is proposed to use a process in which air underpressure is introduced between a record and its support, such as aturntable or another record lying underneath, to facilitate slidingmovement of the record on its support.

It is further proposed to use the force of gravity for moving therecord, this force being created through a slight inclining of therecord supporting table or tables.

It should be particularly understood that the interposing of the airfilm makes it practical to use the force of gravity for sliding therecord from one table to another, the air film serving the purpose, notonly of breaking contact between two adjacent records so as to preventinjury to the grooves of the records, but also that of furnishing ananti-friction bearing for the record to be moved, whereby the latterwill respond to a very slight inclination.

And finally, it is proposed to provide certain other improvements indetails of construction, as well as in the general plan to render mybasic idea available for practical purposes.

Further objects and advantages of my invention will appear as thespecification proceeds, and the novel features of my record changer willbe fully defined in the claims hereto attached.

The preferred form of my invention is illustrated in the accompanyingdrawings forming part of this application, in which:

Figure 1 shows a vertical longitudinal section through the mainoperating mechanism of my record changer;

Figure 2, a top plan view of the record changer;

Figure 3, a horizontal section taken along line 33 of Figure 1;

Figure 4, a detail view of a microphone pick-up arm and its operatingmechanism;

Figure 5, a vertical section through the armoperating mechanism;

Figure 6, a horizontal section taken along line 6-6 of Figure 1; and.

Figure '7, a wiring diagram explaining the sequence of operations,

While I have shown only the preferred form of my invention, I wish tohave it understood that various changes or modifications may be madewithin the scope of the claims hereto attached, without departing fromthe spirit of the invention.

Referring to the drawing in detail, my apparatus may be accommodated inany suitable cabinet I, which may be rectangular in form and maycomprise a bottom 2, end walls 3 and side walls 4. A top 5 for thecabinet is formed with a large opening 6 adapted to accommodate and giveaccess to the records and the main working mechanism.

A base board 1 of any suitable width is hinged to one of the end walls,as at 8 and extends substantially through the length of the cabinet inspaced relation to the bottom of the same, and its free end is supportedon a cam 9 secured upon a large wheel I0 adapted to be driven by themotor ll. 1

Rotation of the cam through one-half of a revolution causes the baseboard to dip or tilt, while a further rotation through one-half arevolution causes the base board to return to horizontal position.

The base board carries a U-shaped wall l2 which serves as a guide forguiding the records from one table to another, as will be more fullydescribed hereinafter. The upper portion of the guide may be providedwith a suitable felt lining as indicated at I3.

The base board further carries, intermediate its length, a post 14,which pivotally supports a beam l5 having two forked ends l6 and l! onwhich the table assemblies rest.

My apparatus comprises two table assemblies, one for the rotary table 29adapted to carry a stack of records 2| to be played, and one for thenon-rotating table 22 adapted to receive the records which have beenplayed.

The two table assemblies are supported on the ends of the beam l5 bymeans of cupped discs 23-24, and the non-rotating table assembly isweighted, as at 25, to be always heavier than the rotating tableassembly, even if all the records are stacked on the latter.

The supporting means for the non-rotating table assembly comprises atube 26 rising from the base board and secured thereto by means of aholding plate 21 fixed to the underside of the base board by means ofrivets 28, and a tube 29 de-' pending from the table and telescoped onthe tube 28.

An air tube 30 extends centrally through thetubes 26 and 29, andconnects, below the base board, with a main air tube 3 l. The upper endof the air tube 39, which is fixed in its position, is on a level withthe top of the table when the latter is in its uppermost position, or ona level with the topmost record placed on the table, so as to serve as acentering pin for the records. The tube terminates in a small orifice orlet, as at 32, for allowing air to escape therethrough.

The table 22 is lowered stepwise, by the thickness of one record,Whenever record is received on the table. The apparatus brin ing aboutthis effect comprises a stepped block 33 having steps 34 correspondingin depth to the thickness of a record, a foot 35 depending from the tube29 and adapted to rest on one of the steps, and op rating means for theblock, whereby the latter is pulled to the left by the width of one stepeach time a record is received on the table.

The operating means for the block comprise an electromagnet 36 pullingagainst spring 31.

The core 3? ofthe electro-ma'gnet. which has a bend to limit its inwardmotion, terminates in an arm 38 running alongside of the block, and thearm and the block are provided with suitable pawl and ratchetarrangement til-Ail, whereby the block is pulled to the left by thewidth of one step each time the electro-magnet is energized. A spring4!! tends to push the core outward for a new bite.

The foot 35 bearing against the vertical wall of each step serves as astop for holding the block in position after each move. The block isformed with a lengthwise slot 49 by means of which it is made tostraddlethe tube 26, and movement toward the right beyond the extremeposition shown in Figure 1 is prevented by the end wall of the slot. 7

, The rotary or turntable assembly includes a tube rising from the baseboard 1, a motor assembly 46 mounted underneath the turntable andcomprising a non-rotary part 4? and a rotary part 48, a tube 49projecting downwardly from the non-rotary part of the motor andtelescoped over the tube 45, a third tube 5!! rising from the concavedisc 24 and telescoped over tube 49, ,5

spring means 5| for urging the concave disc and non-rotary part of themotor apart, and releasable means 52 for locking tube 58 to tube 49 andfor holding the disc 24 and the non-rotary part of the motor in fixedrelation.

The contacting faces of the tubes 4.5, 49 and 50 are made non-circularor polygonal, so as to prevent relative rotation and to hold the part 4!of the motor against rotation.

The motor 46 may be made of any suitable type, and is here shown ascomprising, in its nonrotating part, a laminated core disc 52 and aseries of coils 53 supported on arms 54 projecting from the upper end ofthe tube 49; and, in its rotary part 48, a laminated ring rotor, securedupon the lower face of the turntable 2E). The latter has a dependingannular flange 55 resting on the upper end of the tube 49, which issuitably widened to furnish a bearing surface.

The means 52' for releasably IOOkihg the tube 50 to tube 49 comprise arack 56 on tube 49, a pinion 51 mounted on tube 5i; to mesh with therack, and a solenoid 58 having a plunger 59 normally locking the pinionagainst rotation. When the solenoid is energized, the plunger iswithdrawn and relative adjustment may be made between the two tubes. Theswitch 95 for the solenoid is arranged for convenient manual opera mu.

Thus, normally, the concave disc 24, the tubes 49 and 50, and thenon-rotating part of the motor form a rigid assembly, movable as a unit,but the length of this unit may be adjusted, depending upon the numberof records used, to bring the top record into the proper position with.re spect to the remainder of the apparatus when the beam i5 is in thestarting position, shown in Figure 1.

When in playing position, the top record should be located immediatelyabove the top plane of the table 22, or if the latter carries records,above the top plane of the uppermost record carried thereby.

An air tube (it extends centrally through the tube 35, the table and therecord assembly thereon, and is connected, through a flexible hose 8!,with the main air tube 3i It is normally urged upward to come flush withthe top face of the uppermost record, by means of a spring 62 bearing atone end upon a cage 53 secured to the bottom face of the base board 7?,and at its upper end upon a disc 64' secured upon the air tube.

When the topmost record is to be removed, by the sliding motiondeveloped in the invention,

the air tube has to be retracted by the thickness of the record, andthis is accomplished by means of a solenoid B5 acting on a coupling 66of magnetizable material, this coupling being connected to the hose 6|by means of a nipple 6i of nonmagnetizable material.

The air tube Gil is formed with a reduced orifice or nozzle 68 at itsupper end.

A third air tube H3 rises from the main tube 3i along the edge of thetable 252 nearest the cabinet wall to which the base board 7 is pivoted.

This tube is provided with a lateral nozzle ii directed at the planebetween the two uppermost records and is intended to biow a film of airunderneath the topmost record.

The film of air will relieve binding contact between the uppermostrecord and the next one and will start sliding movement of the recordtoward the second table as soon as the baseboard is tilted. The recordthus practically floats on air, all friction is eliminated and therecord will start moving in response to a very slight gravitationalforce.

The space between the two tables is occupied by a cover plate 12, thetop of which is on a level with the top or table 22 (when empty) and thetop of the second record on table 20, so that the top faces of the table22, the cover plate i2 and the second record form a common plane whichthe top record may slide, supported by the air cushion, from one tableto the other, when the common plane is tilted.

The cover plate 12 has two air tubes projecting therethrough on oppositesides of the centerline of the two tables. The latter tubes connect withthe main tube 3| and extend to the top of the cover plate, where theydischarge through nozzle M.

The main air tube is controlled by an electri-- cally operated valve 15.This valve is operated in timed relation to the tilting of the baseboard,

so that when the board is tilted, the air blows between the twouppermost records from tube iii to create an air film or an air floatallows the record to start moving, the tube Gil having been withdrawnsufficiently to clear the record.

As the record slides down the inclined plane formed by the secondrecord, the cover plate 72 and the second table, the air tubes S8, 13and 38 75 successively supply the necessary air to maintain the airfilm, and the record thus easily gravitates upon the table 22, beingguided by the U-shaped guide I2 and its lining which stop the recordwhen it becomes centered over the table 22.

The microphone pickup arm 80' may be mounted in a post I rising from abracket 82, which latter may be secured upon the U-shaped guide I2, atone side of the turn table. The post is revolvable about a pin 83(Figure 4) l and the arm is pivoted in the post with freedom of swingingmovement in a vertical plane.

The post M has a brace 84 projecting over the arm 80, and the bracecarries an electro-magnet 85 disposed above an intermediate section ofthe arm 80. The electro-magnet carries a core 86 of magnetizablematerial and the arm 80 has an insert 81 of the same material rightunderneath the core. The latter also carries a pin 88 projecting throughthe insert and formed with a head underneath the same.

The core 86 has a disc 81 secured thereto, and a bellows 88' connectsthe disc 81 and the lower end of the electro-magnet so as to form acontractible chamber about the core 86, this chamber connecting into thechamber 89 above the core, which latter is closed at the upper end bythe top plate of the electro-magnet. The latter plate has a largeopening 90 with a ball valve 9|, and a restricted orifice 92.

Due to this construction, when the magnet is u chamber freely escapingthrough the check valve As the magnet is de-energized, the insert of arm80 naturally drops away from the core, but the amount of this drop islimited by the head of the pin 88. The core also tends to dropimmediately, but its downward progress is retarded by suction, since thevalve 9| automatically closes and a certain amount of time is consumedin supplying the air needed for the expansion of the bellows through thelimited aperture 92. Thus the arm 89 is lifted quickly, but is let downslowly.

Horizontally, the arm 80 travels from left to right (Figure 2) while therecord is being played, is then lifted by the electro-magnet, swingsback to an initial position (from right to left) by gravity when theentire apparatus is tilted for transferring a record, and is let down tothe new record after the top record has been transferred.

The post M has an arm 93 projecting rearwardly therefrom to close aswitch 94 for energizing the electro-magnet when the arm 80 has reachedthe end of its inward movement.

To prepare for use, the operator first presses down on the turn table 20to bring the concave disc 24 to its lowermost position, as indicated inFigure 1. This will bring the table 22 to its uppermost position, on alevel with the top plate 12, and will cause the spring 31 to pull thestepped block 33 to the right so that foot 35 comesto rest on thehighest step, suitable means being provided for disengaging pawl 39during this operation.

The operator then places the desired number of records on the turn table20, pushes the switch 95' (see Wiring diagram) energizing magnet 58,which unlocks the tube 49 from the tube- 50, and then allows the springI to raise the turn table until the uppermost record is in the correctposition, that is, immediately above the plane of the top plate I2 andthe table 22. The switch is then released.

The sequence of operations may be best explained by means of the wiringdiagram of Figure '7, in which a main line switch is shown at 95,differential relay switches 96, 91, 98 and 99, and special switchmembers I00, MI, and I02, and in which the wires have been lettered asshown.

Assuming that the phonograph is playing, with both switches 95 and 96closed, and the needle reaches the end of the record so as to closeswitch 94, the following operations take place:

1. Current flows through wire a, 93, 94, h, wire p, opening relay ofswitch 96 and back to wire I); switch 96 opens; motor 46 stops.

2. Current flows through wire a, arm 93, 94, closing relay of 91, andwire I); switch 91 closes, and current flows from wire a, through relay91, magnet and back to wire I). Magnet 85 lifts tone arm.

3. Current flows through wire a, arm 93, 94, wire (1, magnet 65, andwire e to b; magnet 65 pulls down air tube 60.

4. Current flows through wire (1, arm 93, 94, wire (1, wire closingrelay of 99; wire 9, and back through c to b; closes switch 99; currentflows from a through 99, magnet I5, and wires 9, e, back to b; magnet I5opens air valve.

5. Current flows from wire a, through 93, 94, wire h, closing relay of98, and to negative lead B; closes switch 98; current flows frompositive lead A through switch 98, motor II, to negative lead B. Motor II turns cam 9.

The record slides over, becomes centered and the tone arm swings fromright to left, opening switch 94, which deengergizes solenoid magnet 65allowing air tube 69 to rise, to act as centering pin for a new toprecord.

6. As the cam reaches lowermost position, contacts close at H, currentflows from a through 2, I0 I, is, opening relay of 99, through g, e toI), opening 99 and stopping flow of air.

'7. Cam lifts platform I on completing one rotation and member I00closes switch I02; temporarily current flows from wire I through I02, m,magnet 36 and back to B; magnet 36 pulls back the stepped block 34.

8. At the same time current flows from I through I02, n, and openingrelay of 98, opening the latter and stopping motor II.

9. At the same time current flows from I through I02, wire 0, andclosing relay of 96 to b, closing switch 96. and starting motor 46.

10. At the same time current flows from 1 through I02, wire q, openingrelay for switch 91, and back to b; switch 91 opens; tone arm drops.

I claim:

1. In a record changer of the character described, two tables adapted tohave records stacked thereon, a tiltable base board having a postthereon, a beam pivoted in the post and having the tables supported onthe ends thereof, means operable for positioning the tables in fixedrelation to the baseboard and at related elevations to allow one recordto slide from one table to the other and means for tilting the baseboard to effect such sliding motion.

2. In a record changer of the character described, two tables adapted tohave records stacked thereon, a tiltable base having a post thereon, abeam pivoted in the post and having the tables supported on the endsthereof, means operable for positioning the tables in fixed relation tothe baseboard and. at related elevatitans-rte alldw-:onerreeordltoeslide:from: 55 91 .5- to the other, means for tilting the base to;-ef-.

feet; suchi slidin motionnand; means operable-for vertically-shiftingthe tables fafter; -arecord has beenttitansferredito again, establishrelated .ele

vationss 3.tIn:-a record changer -oi; the-character de-- scribed; twotables; adapted to: have. records} stacked thereon, a tiltable baseboard having,

acpostwthereon a beam pivoted in the post'and having theitables,supported'onzthe ends thereof, means operable for. positioning thetables in fixed relation to the-jbaseboardgand; at related elevations toallow one record to slide-from one table 0othe other; and means forblowing ai-r;-und erneath the recordto-be moved to relieve friction for;facilitating: the..,sliding movement when the basedc'oard is tiltede.

4. 1115a record)2 changer -of the character. de-

scribed; two; tables adapted to have records stacked thereon, a platformbetween the tables,-

means for "positioning -thetables with respect to the platform toprovide acommon plane =f0r a record to slide from one stack-to.the'other, and means forblowinggiair:underneaththe record at saidcommonplane to relievev friction .for facilitating the sliding movement of therecord .whenthe plane'i -tiltedr 5. In a record changerlof the characterde scribed, two, tables. adapted to. have records stacked. thereon,aplatform between, the tables, meansfor, positioning the tables withrespect to the-platform to (provideacommon plane for a record to slidefrombnestack to the other,-

means for tiltin the common plane. to set, up

a gravitationalforce. for, urging. the record to, move,,,and meansforblowing. air underneathv the record to eliminate. frictional..resistanceto.

the transfer.

6.. In.a..record. changer of the character described.,,two tablesadapted. to 1 have records stacked thereon a platformbetween the. t l s,means for positioning the tables with respect to theplatform toprovide acommon plane for a record to slide from onestack to the other, means.

fortiltingthe common planeto set upa gravitationalfforcefor. urging therecordto move, and.

meansfior. lcw sg irru dern a e o d o.

iminate fr onalsresistance o transfer, the :said means:comprising meansfor injecting air underneath; the-recordprogressively at the 53upperpend oftherecordand at spaced points during its travel 7.;Ina:recordchanger of -the character described, two tables--. adaptedrto haverecords stacked thereon, a platform between the tables,

:meansior positioning the-tables with respect to the platform toproviole acommon plane for a record: to slidefrom-onestack to the other,means for -tilting the ;commonplane-;to.- set up a gravitationalforcefqr;urg-ingthe-record to move, and means; for -blowingairunderneath the record to eliminate -fr ictionalgresistanceto thetransfer; the saidg means comprising means -for injectting airunderneath itherrecord progressively at the upper end of therecord andat spaced points during its travel, and-:lateralsupporting meansbeingprovided for guiding; the record from one table to,the-othe1.--

MILTON A.- WALKER.

REFERENCES, CITED The-fo1lowing;ref.erences-are of record in the file.of patent:-

UNITED STATES PATENTS

